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6.30.2011

Our star is quiet this late few days. After a interesting and active period its now
calm. Still a solar wind stream is heading for Earth expected to reach on July 2nd.
Minor geomagnetic storms are possible when the stream arrives and auroras will be dancing in the northern night sky.

Any sulfurous molecules that astronomers spot on alien worlds might be a way to reveal whether or not those distant planets host life, researchers suggest.

This chart explains how astronomers measure the signatures of chemicals in the atmospheres of planets that orbit other stars, called exoplanets. Image credit: NASA/JPL-Caltech

On Earth, microbes can live off the energy available in sulfurous molecules that volcanoes release, essentially "breathing" these compounds the way humans breathe oxygen. If a similar kind of metabolism evolved on an extrasolar planet, the sulfurous molecules detected in the atmosphere of that world might help reveal the presence of alien life, said researcher Renyu Hu, a doctoral student in planetary science at MIT.

By tracking atmospheric features on Neptune, a UA planetary scientist has accurately determined the planet's rotation, a feat that had not been previously achieved for any of the gas planets in our solar system except Jupiter.

Voyager 2 captured this image of Neptune in 1989.Credit: NASA

A day on Neptune lasts precisely 15 hours, 57 minutes and 59 seconds, according to the first accurate measurement of its rotational period made by University of Arizona planetary scientist Erich Karkoschka.

His result is one of the largest improvements in determining the rotational period of a gas planet in almost 350 years since Italian astronomer Giovanni Cassini made the first observations of Jupiter's Red Spot.

"The rotational period of a planet is one of its fundamental properties," said Karkoschka, a senior staff scientist at the UA's Lunar and Planetary Laboratory. "Neptune has two features observable with the Hubble Space Telescope that seem to track the interior rotation of the planet. Nothing similar has been seen before on any of the four giant planets."

The discovery is published in Icarus, the official scientific publication of the Division for Planetary Sciences of the American Astronomical Society.

Astronomers have discovered a new comet that could be visible to the naked eye in early 2013.

In this series of images, the comet C/2011 L4 (PANSTARRS) can be seen moving across the field of view CLICK on Image. Credit: Institute of Astronomy, University of Hawaii

Astronomers at the University of Hawaii at Manoa have discovered a new comet that they expect will be visible to the naked eye in early 2013.

Originally found by the Pan-STARRS 1 telescope on Haleakala, Maui, on the night of June 5-6, it was confirmed to be a comet by UH astronomer Richard Wainscoat and graduate student Marco Micheli the following night using the Canada-France-Hawaii Telescope on Mauna Kea.

A preliminary orbit computed by the Minor Planet Center in Cambridge, Mass., shows that the comet will come within about 30 million miles (50 million km) of the Sun in early 2013, about the same distance as Mercury. The comet will pose no danger to Earth.

Wainscoat said, “The comet has an orbit that is close to parabolic, meaning that this may be the first time it will ever come close to the Sun, and that it may never return.”

The comet is now about 700 million miles (1.2 billion km) from the Sun, placing it beyond the orbit of Jupiter. It is currently too faint to be seen without a telescope with a sensitive electronic detector.The comet is expected to be brightest in February or March 2013, when it makes its closest approach to the Sun. At that time, the comet is expected to be visible low in the western sky after sunset, but the bright twilight sky may make it difficult to view.

This image of ULAS J1120+0641, a very distant quasar powered by a black hole with a mass two billion times that of the Sun, was created from images taken from surveys made by both the Sloan Digital Sky Survey and the UKIRT Infrared Deep Sky Survey. The quasar appears as a faint red dot close to the centre. This quasar is the most distant yet found and is seen as it was just 770 million years after the Big Bang.Credit:

ESO/UKIDSS/SDSS

European astronomers have discovered the most distant quasar yet discovered from observations made with the telescope's long-range European Southern Observatory (ISO) on Cerro Paranal in Chile, and other telescopes. According to the results of the study facilitated Efe by Richard Hook, spokesman for the IT Garching, southern Germany, it is the brightest object so far discovered in the early universe, which is powered by a black hole that has two billion times the mass of the Sun

Saturn's rings cut across this view of the planet's largest moon, Titan. Dark albedo features on Titan (5,150 kilometers, or 3,200 miles across) and the moon's north polar hood are visible here.

This view looks toward the southern, unilluminated side of the rings from just below the ringplane and toward the Saturn-facing side of Titan. North on Titan is up.

The image was taken with the Cassini spacecraft narrow-angle camera on May 12, 2011 using a spectral filter sensitive to wavelengths of near-infrared light centered at 938 nanometers. The view was acquired at a distance of approximately 2.3 million kilometers (1.4 million miles) from Titan and at a Sun-Titan-spacecraft, or phase, angle of 11 degrees. Image scale is 14 kilometers (9 miles) per pixel.

Calling all amateur star gazers: Scientists need your help. A team from Southern Illinois University in Edwardsville has developed the website IceHunters (http://www.icehunters.org), which challenges the public to discover potential destinations for a NASA mission at the very edge of the solar system set to happen around 2015.

The University of Arizona's College of Optical Sciences has been awarded a multi-million dollar contract by the Association of Universities for Research in Astronomy, or AURA, to polish the 4.2-meter primary mirror for the Advanced Technology Solar Telescope, or ATST.

When operational in Hawaii, the ATST will become the world's largest solar telescope. This glass mirror will serve as the primary focusing element to create high-resolution images of the fine scale structure of the sun.

The curved mirror will be manufactured such that it can be adjusted to suit the surrounding conditions using actuators and controlled ventilation on its backside. (Image: AURA)

Asteroid 2011 MD flew past Earth on Monday, June 27th. At closest approach the ~10-meter space rock was only 12,000 kilometers (7,500 miles) above the planet's surface. NASA analysts said there was no chance it would strike Earth, and indeed it didn't.

Astronomers around the world monitored the flyby. Using a remotely-controled telescope in Cerro Tololo, Chile, Joe Pollock of Appalachian State University obtained this light curve:

"The brightness variations are due to the asteroid's spin," explains Pollock. "It appears to be rotating with a 23.3 or 11.6 minute period."

An excellent video recorded by Andre Paquette of Ottawa, Canada, shows the brightness of the asteroid oscillating as it races among the stars. "My light curve is a good match to Cerro Tololo's," says Paquette.

NASA's Lunar Reconnaissance Orbiter (LRO) has forever changed our view of the moon, literally bringing it into sharper focus and showing us the whole globe in unprecedented detail.

A LOLA digital elevation map compiled in late 2009 (right) is compared to the Unified Lunar Control Network (ULCN) 2005, a painstakingly constructed map based on the best available data at the time, compiled by the U.S. Geological Survey. (Credit: NASA's Goddard Space Flight Center's Science Visualization Studio/Massachusetts Institute of Technology)

This rich new portrait has been rendered by LRO's seven onboard instruments, which together have delivered more than 192 terabytes of data, images and maps -- the equivalent of nearly 41,000 typical DVDs. "This is a tremendous accomplishment," says Douglas Cooke, Associate Administrator of the Exploration Systems Mission Directorate at NASA Headquarters, Washington. "The exploration phase of the mission delivered a lot more than it originally promised, and that's been just the beginning for LRO."

Dramatic plumes (cloudy, white areas), both large and small, spray water ice out from many locations along the famed "tiger stripes" near the south pole of Saturn's moon Enceladus. Image credit: NASA/JPL/SSI

NASA's Cassini spacecraft has discovered the best evidence yet for a large-scale saltwater reservoir beneath the icy crust of Saturn's moon Enceladus. The data came from the spacecraft's direct analysis of salt-rich ice grains close to the jets ejected from the moon.